A 20-GSamples/s Track-Hold Amplifier in InP DHBT technology

A fully differential 20 Gsample/s Track and Hold Amplifier with 20 GHz large-input-signal bandwidth is designed and fabricated in 210 GHz-fT-InP-DHBT on a 1.6 x 1.4 mm
²
chip. Spectral measurements in track mode give an SNR, a THD, and a SFDR respectively of 65 dB, -38 dB and -38 dB for input frequency up to 9 GHz and input voltage up to 0.5 Vpp. This THD is equivalent to 6 ENOB. Time domain measurements illustrate 20 GHz sampling with 2 and 5 GHz sinusoidal input signals.